mysql too many open connections问题解决方法

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mysql too many open connections问题解决方法_MySQL

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Jun 01, 2016 pm 01:12 PM

mysqlconsoleserver

曾经以为在my.cnf写入max_connections = 2000
就可以改变mysql的最大并发量，今天查到一个命令，发现服务器的mysql最大连接数为151.

控制台，连接上mysql

show variables;
这条命令可以看到所有基础配置

如果单独看max_connections可以这样

show variables like 'max%';
+―――――――――-+――――+
| Variable_name | Value |
+―――――――――-+――――+
| max_allowed_packet | 1048576 |
| max_binlog_cache_size | 4294963200 |
| max_binlog_size | 1073741824 |
| max_connect_errors | 10 |
| max_connections | 151 |
| max_delayed_threads | 20 |
| max_error_count | 64 |
| max_heap_table_size | 16777216 |
| max_insert_delayed_threads | 20

151 好像是lampp默认的最大连接数。

my.cnf里大致这样写的

max_connections=2000
# The MySQL server
[mysqld]
port            = 3306
socket          = /Applications/XAMPP/xamppfiles/var/mysql/mysql.sock
改完以后

# The MySQL server
[mysqld]
max_connections=2000
port            = 3306
然后把max_connections=2000移动到[mysqld]下面，重启动mysql

+―――――――――-+――――+
| Variable_name | Value |
+―――――――――-+――――+
| max_allowed_packet | 1048576 |
| max_binlog_cache_size | 4294963200 |
| max_binlog_size | 1073741824 |
| max_connect_errors | 10 |
| max_connections | 2000 |
| max_delayed_threads | 20 |
| max_error_count | 64 |
| max_heap_table_size | 16777216 |
| max_insert_delayed_threads | 20

就好了。

说明这配置必须在[mysqld]下面，才有用。

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